More and more computing applications are being implemented using large data centers, some of which may contain thousands of servers with different performance and power consumption characteristics. At any given data center, time-varying workloads from hundreds or thousands of clients may be executed, and as a result the resource consumption levels may vary substantially over time. At some points in time, a given subset of the computing resources housed a data center may be heavily used, while at other times, the same resources may be lightly used. Some provider networks may support numerous network-accessible multi-tenant services at dozens or hundreds of data centers distributed around the world, where at least some of the services may rely on utilizing each other's resources, making predictions about resource usage hard.
Power costs (e.g., the costs of electrical power consumed by various computing devices, and by the cooling infrastructure at the data center) can comprise a substantial proportion of the operating expenses for data center maintenance. In addition to purely financial considerations, data center operators may also wish to reduce power consumption as much as possible for environmental reasons, while still providing the best possible service to the clients utilizing the data center. For at least some types of applications, tradeoffs may be possible between power consumption at various computing devices (which may correspond to the utilization levels of the devices) and application performance.
Some data centers may house many different types of computing equipment and related infrastructure components, and the equipment may typically change over time, as may the cost of obtaining electrical power. The dynamic nature, complexity and size of a data center's workload, when combined with the complexity and size of the inventory, may often complicate attempts to reduce or optimize power usage.
While embodiments are described herein by way of example for several embodiments and illustrative drawings, those skilled in the art will recognize that embodiments are not limited to the embodiments or drawings described. It should be understood, that the drawings and detailed description thereto are not intended to limit embodiments to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope as defined by the appended claims. The headings used herein are for organizational purposes only and are not meant to be used to limit the scope of the description or the claims. As used throughout this application, the word “may” is used in a permissive sense (i.e., meaning having the potential to), rather than the mandatory sense (i.e., meaning must). Similarly, the words “include,” “including,” and “includes” mean including, but not limited to.